Estimation of Type IV Cracking Tendency in Power Plant Steels

Type IV cracking in ferritic power plant steels

There have been concerted world wide efforts to develop steels suitable for use in efficient fossil fired power plants. Ferritic alloys containing between 9 and 12 wt-% chromium are seen as the most promising materials in this respect, especially for thick walled components such as headers and the main steam pipe in boilers. However, the performance of the improved steels has often not been rea...

Modelling precipitation sequences in power plant steels

New kinetic theory capable of dealing with the simultaneous precipitation of several phases has been applied to a variety of creep resistant power plant steels. It has been demonstrated that the model has the ability to predict the vast differences in precipitation kinetics reported in the published literature for power plant steels. New experimental results on precipitation in a 9Cr 1 Mo type ...

Fault Type Estimation in Power Systems

This paper presents a novel approach for fault type estimation in power systems. The Fault type estimation is the first step to estimate instantaneous voltage, voltage sag magnitude and duration in a three-phase system at fault duration. The approach is based on time-domain state estimation where redundant measurements are available. The current based model allows a linear mapping between the m...

Welding residual stresses in ferritic power plant steels

Many of the degradation mechanisms relevant to power plant components can be exacerbated by stresses that reside within the material. Good design or structural integrity assessments require therefore, an accounting of residual stresses, which often are introduced during welding. To do this it is necessary to characterise the stresses, but this may not be possible in thick components using non-d...

Modelling Simultaneous Alloy Carbide Sequence in Power Plant Steels